From my picture post on HT-General: http://www3.sympatico.ca/john.mckenzie
Scott asked the following:
"Could you take a few moments to describe the masking system
that you use? I am very interested in the type of magnets and the felt panels. Do they fold or roll? What were the panels structure made of and how did you apply the felt? You might want to respond in the Screen forum, you should get an excellent response there."

The permanent screen frame is particle board 5/8 x 3 x appropriate length for top and sides. The bottom is wider to accommodate speakers that are mounted at either end just below the screen. The bottom panel is supported on the wall by 3 small angles at bottom and velcro'ed to wall at the top. Other 3 pieces are velcro'ed to wall only. All are felt covered, using double-faced carpet tape on the front side, stapled to the back and covered with duct tape to finish. A warm iron was used to "set" the felt on the carpet tape. I do not recommend the use of glue or spray adhesive due to poor bonding and handling control.
The masking panels are of "masonite" (hardboard) 1/8 or 3/16? thick and again the appropriate width and length. The 2 side panels are used to frame the 4:3; the 2 top and bottom are used to frame the 16x9 and 2.35:1 ratios (2 positions for panels). They were covered in same felt, using carpet tape both sides, as too thin for stapling on the back, and the duct tape. The panels do not fold or roll. They are "stuck" to the permanent screen frame using steel washers and "rare earth" magnets purchased from: http://www.leevalleytools.com
The washers (4) are screwed to the permanent frame. The magnets (3 stacked at each point) are epoxy'ed to the masking panel (1 magnet only - other 2 just "stick"). You can see that I used quite a few magnets!!! I'm not sure what the mental health problems might be if you stand too close for a long time!!! http://www.avsforum.com/ubb/biggrin.gif The horizontal panels that rest in 2 positions have 2 stacks at each end of the panel, the vertical panels have only 1 stack at each end. When 1 pair of panels is in use, the other is stored on the floor under the sofa. That's about it.
All the best. John